Medical costs associated with cardiovascular events among high-risk patients with hyperlipidemia

Figures & data

Table 1 Demographic and clinical characteristics of CHD-RE patients

Demographic characteristics	CHD-RE
	N=38,609
	N/mean	%/SD
Age (mean, SD)	57.0	6.0
Age cohort (N, %)
18–34	140	0.4%
35–44	1,511	3.9%
45–54	9,285	24.0%
55–64	27,673	71.7%
Male (N, %)	26,659	69.0%
Urban (N, %)	30,654	79.4%
Geographic region (N, %)
North East	5,644	14.6%
North Central	10,867	28.1%
South	16,895	43.8%
West	4,907	12.7%
Unknown	296	0.8%
Insurance plan type (N, %)
Comprehensive/indemnity	2,805	7.3%
EPO/PPO	22,236	57.6%
POS/POS w/capitation	4,065	10.5%
HMO	6,181	16.0%
CDHP/HDHP	1,370	3.5%
Missing/unknown	1,952	5.1%
Risk cohort criteria (N, %)
Diabetes	32,549	84.3%
Peripheral arterial disease	6,715	17.4%
Coronary artery disease	5,124	13.3%
Abdominal aortic aneurysm	954	2.5%
Deyo-Charlson comorbidity index (mean, SD)	2.0	1.6
Comorbid conditions (N, %)
Hypertension	25,911	67.1%
Dyslipidemia	22,900	59.3%
Respiratory disease	17,507	45.3%
Renal disease	6,344	16.4%
Arthritis (OA/RA)	6,483	16.8%
Statin use (N, %)	34,569	89.5%

Note: Risk cohort criteria are not mutually exclusive; therefore, proportions will total >100%.

Abbreviations: CHD-RE, coronary heart disease risk equivalent; SD, standard deviation; HMO, health maintenance organization; POS, point of service; PPO, preferred provider organization; EPO, exclusive provider organization; CDHP, consumer-driven health plan; HDHP, high deductible health plan; OA, osteoarthritis; RA, rheumatoid arthritis.

Figure 1 Patient proportions of index cardiovascular event.

Notes: Multiple events within the same index hospitalization were classified according to the following hierarchy, which was created to take into account the principal reason for the hospitalization: myocardial infarction, stroke, unstable angina, transient ischemic attack, percutaneous coronary intervention, and coronary artery bypass graft.
Abbreviations: CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention.

Figure 2 Proportion of patients with second and third CV events stratified by first CV event.

Notes: Revascularization includes both coronary artery bypass graft and percutaneous coronary intervention.
Abbreviations: CV, cardiovascular; MI, myocardial infarction; UA, unstable angina; TIA, transient ischemic attack; Revasc, revascularization.

Figure 3 First quarter costs by CV event as a first, second, or third event.

Notes: *indicates a sample size of <50. Heart failure could only be a second or third event among the study population; therefore, costs for heart failure as a first event are not included in the figure.
Abbreviations: CV, cardiovascular; MI, myocardial infarction; UA, unstable angina; TIA, transient ischemic attack; CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention; HF, heart failure.

Table 2 Subsequent CV events among CHD-RE patients

Subsequent CV event	CHD-RE
	N=38,609
	Number	%
Presence of second CV event (N, %)	5,782	15.0%
Type of second CV event (N, %)
MI	1,596	4.1%
Stroke	796	2.1%
Unstable angina	72	0.2%
TIA	277	0.7%
Heart failure	17	0.0%
Revascularization (CABG and PCI)	3,024	7.8%
Presence of third CV event (N, %)	1,078	2.8%
Type of third CV event (N, %)
MI	267	0.7%
Stroke	159	0.4%
Unstable angina	19	0.0%
TIA	64	0.2%
Heart failure	2	0.0%
Revascularization (CABG and PCI)	567	1.5%

Abbreviations: CV, cardiovascular; CHD-RE, coronary heart disease risk equivalent; MI, myocardial infarction; TIA, transient ischemic attack; CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention.

Table 3 Frequency and acute incremental costs of first, second, and third CV events

First CV event	CHD-RE
	N=38,609
Myocardial infarction (n, %)	9,963, 25.8%
Incremental postindex cost (mean, SD)	$44,808, $48,122
Stroke (n, %)	5,218, 13.5%
Incremental postindex cost (mean, SD)	$34,158, $48,759
Unstable angina (n, %)	959, 2.5%
Incremental postindex cost (mean, SD)	$18,902, $32,628
Transient ischemic attack (n, %)	2,602, 6.7%
Incremental postindex cost (mean, SD)	$13,982, $22,489
CABG (n, %)	7,875, 20.4%
Incremental postindex cost (mean, SD)	$74,562, $55,642
PCI (n, %)	12,125, 31.4%
Incremental postindex cost (mean, SD)	$35,323, $34,658
Second CV event	N=5,782
Myocardial infarction (n, %)	1,596, 4.1%
Incremental postindex cost (mean, SD)	$46,484, $61,032
Stroke (n, %)	796, 2.1%
Incremental postindex cost (mean, SD)	$42,050, $57,587
Unstable angina (n, %)	72, 0.2%
Incremental postindex cost (mean, SD)	$18,808, $30,323
Transient ischemic attack (n, %)	277, 0.7%
Incremental postindex cost (mean, SD)	$14,602, $22,046
Heart failure (n, %)	17, 0.0%
Incremental postindex cost (mean, SD)	$83,198, $65,544
CABG (n, %)	707, 1.8%
Incremental postindex cost (mean, SD)	$84,971, $68,371
PCI (n, %)	2,334, 6.0%
Incremental postindex cost (mean, SD)	$33,844, $38,571
Third CV event	N=1,078
Myocardial infarction (n, %)	267, 0.7%
Incremental postindex cost (mean, SD)	$43,525, $61,945
Stroke (n, %)	159, 0.4%
Incremental postindex cost (mean, SD)	$47,309, $75,098
Unstable angina (n, %)	19, 0.0%
Incremental postindex cost (mean, SD)	$15,900, $18,499
Transient ischemic attack (n, %)	64, 0.2%
Incremental postindex cost (mean, SD)	$17,285, $23,120
Heart failure (n, %)	2, 0.0%
Incremental postindex cost (mean, SD)	$40,438, $1,155
CABG (n, %)	123, 0.3%
Incremental postindex cost (mean, SD)	$102,907, $107,390
PCI (n, %)	444, 1.1%
Incremental postindex cost (mean, SD)	$34,341, $34,078

Notes: Incremental acute costs were calculated as the difference between the first quarter total postindex cost and the patient’s quarterly baseline cost. All currency is USD.

Abbreviations: CV, cardiovascular; CHD-RE, coronary heart disease risk equivalent; SD, standard deviation; CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention.

Figure 4 Quarterly CV event costs through year three as a proportion of first quarter costs by index CV event.

Abbreviations: CV, cardiovascular; MI, myocardial infarction; UA, unstable angina; TIA, transient ischemic attack; CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention; Q1, first quarter; Q2, second quarter; Q3, third quarter; Q4, fourth quarter; Q5, fifth quarter; Q6, sixth quarter; Q7, seventh quarter; Q8, eighth quarter; Q9, ninth quarter; Q10, tenth quarter; Q11, eleventh quarter; Q12, twelfth quarter.

Table 4 Proportion and adjusted incremental cost of fatal first CV events

First CV event	CHD risk equivalent
	Number of patients with event	Deaths	%	Observed costs		Adjusted costs		Adjusted incrementa	Lower l 95% CI	Upper 95% CI	P-value
				Survive	Die	Survive	Die
Myocardial infarction	4,220	117	2.8%	$44,753	$54,580	$45,153	$54,001	$8,848	$1,375	$17,522	0.0185
Stroke	2,220	98	4.4%	$33,601	$48,895	$34,39	$48,556	$14,258	$5,387	$24,229	0.0003
Unstable angina	362	4	1.1%	$20,592	$70,304	$20,947	$60,651	$39,704	$2,326	$135,090	0.0275
Transient ischemic attack	1,001	6	0.8%	$13,321	$24,004	$13,376	$22,979	$9,003	($1,501)	$28,352	0.1106
CABG	3,641	36	1.0%	$73,346	$124,024	$73,342	$126,391	$52,849	$30,070	$80,643	<0.0001
PCI	5,234	34	0.6%	$34,800	$60,565	$35,210	$55,650	$21,440	$9,663	$36,314	<0.0001

Notes: Statistical analysis was performed using generalized linear models with gamma-distributed error and log link. All currency is USD.

Abbreviations: CV, cardiovascular; CHD, coronary heart disease; CI, confidence interval; CABG, coronary artery bypass graft; PCI, percutaneous coronary intervention.